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21.
Background P-wave dispersion (PWD), a measure of heterogeneity of atrial refractoriness, is defined as the difference between the maximum and minimum P-wave duration. In patients with severe aortic stenosis (AS), P-wave duration and PWD were shown to be increased, indicating atrial electrical remodeling. However, the effect of transcatheter aortic valve replacement (TAVR) on P-wave morphology has not been established yet. The aim of this study is to assess the short and long-term effects of TAVR with two types of bioprosthetic valves on P-wave duration and PWD in association with left atrial (LA) size. Methods Fifty-two (36 female) eligible patients in sinus rhythm who underwent transfemoral TAVR between June 01, 2012 and July 31, 2014 with either a Medtronic CoreValve (MCV) (n = 32) or an Edwards SAPIEN XT Valve (n = 20) were enrolled. Standard 12-lead electrocardiogram and echocardiographic evaluations were performed pre-procedurally, post-TAVR day one and 6 months post-TAVR. P-wave duration and PWD were measured and correlation analyses with echocardiographic variables were performed. Results P-wave duration and PWD were significantly decreased on post-TAVR day one (P < 0.05). They continued to decrease during the six month follow-up period, but were not significantly different from short-term values (P > 0.05). The decrease of LA diameter was found significant at the sixth-months of follow-up (P < 0.05). These changes were independent from the types of bioprosthetic valves implanted (P > 0.05). A positive correlation was detected between minimum P-wave duration and maximum aortic valve gradients at post-TAVR day one (r = 0.297, P = 0.032). Conclusions P-wave duration and PWD were significantly reduced early after TAVR indicating early reverse atrial electrical remodeling. Moreover, structural reverse remodeling of atrium was detected at the 6-months of follow-up. The effects of two types of bioprosthetic valves on atrial remodeling were similar.  相似文献   
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Objectives:To evaluate and compare the dental and skeletal changes with conventional and miniscrew-supported maxillary expansion appliances in adolescents.Materials and Methods:Forty patients were divided into two groups, with one group receiving a tooth-borne expander and the other group receiving an expander supported by four miniscrews (bone-borne). Multiplanar coronal and axial slices obtained from cone-beam computed tomography images were used to measure the changes in transverse skeletal widths, buccal bone thickness, tooth inclination, and root length. Paired t-tests and independent-sample t-tests were used to compare the two expansion methods.Results:Bone-borne expansion increased the maxillary suture opening more than 2.5 times than tooth-borne expansion both anteriorly and posteriorly. Between the maxillary first premolars, sutural expansion accounted for 28% and 70% of the total transverse width increase in the tooth-borne and bone-borne expander groups, respectively. Similarly, 26% and 68% of the total expansion was of skeletal nature in the tooth-borne and bone-borne expander groups between the maxillary first molars. The pattern of expansion was variable, with most of the patients in both groups demonstrating a triangular-shaped sutural opening that was wider anteriorly. Subjects in the conventional group experienced significantly more buccal bone reduction and greater buccal inclination of the teeth. No significant differences were observed for root length measurements between the two groups.Conclusion:Use of bone-borne expansion in the adolescent population increased the extent of skeletal changes in the range of 1.5 to 2.8 times that of tooth-borne expansion and did not result in any dental side effects.  相似文献   
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Myocardial inflammation is one of the commonest mechanisms in cardiomyopathy (CMP). Mannose binding lectin (MBL) is a key molecule in innate immunity, while macrophage migration inhibitory factor (MIF) is a constitutive element of the host defenses. We investigated the possible association between polymorphisms of MBL2 and MIF genes and CMP in Turkish children. Twenty-children with CMP and 30 healthy controls were analyzed for codon 54 A/B polymorphism in MBL, and -173 G/C polymorphism in MIF genes by using PCR-RFLP methods. No significant difference was found between genotypes and alleles of MBL2 gene codon 54 A/B polymorphism in patients and controls (p>0.05). However, serum uric acid levels was found higher in dilated CMP patients with AA genotype. Frequency of MIF -173 CC genotype was significantly higher in patients (p<0.05), and sodium levels were higher in patients with MIF -173 CC genotype. This study is the first to investigate the MBL and MIF gene polymorphisms in Turkish children with CMP. We conclude that CC genotype of MIF (-173) polymorphism may be a risk factor for CMP patients. However, further studies with larger samples are needed to address the exact role of this polymorphism in CMP.  相似文献   
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Purpose  

Prophylactic knee braces are largely used in the prevention of ligament injuries, but their effectiveness on performance are still controversial. The aim of this study was to determine which brace was the most effective on functional performance.  相似文献   
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Prosthetic management of partial edentulism can be challenging with the presence of limited interocclusal space. The extrusion of opposing teeth combined with the alveolar extrusion of the edentulous areas reduces the space needed for fabricating a removable or fixed prosthesis when edentulous areas are present in the maxilla. This clinical report describes the treatment provided to a patient who presented with a limited interocclusal space on the posterior right quadrant. Before prosthetic rehabilitation, mandibular right posterior teeth were intruded, and the maxillary right posterior alveolar crest was reduced by alveoloplasty. After gaining adequate space, prosthetic rehabilitation was completed with a maxillary removable partial denture. During the 2‐year follow‐up period, the patient's chewing functions and physical appearance improved, and no complications occurred.  相似文献   
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IntroductionLymphedema is the most important complication seen after breast cancer surgery. The study aimed to evaluate pain, shoulder-arm complex function, and scapular function in women who developed lymphedema after breast cancer surgery and to compare these with women without lymphedema.Materials and MethodsFifty women with lymphedema (age, 54.34 ± 9.08 years; body mass index, 30.10 ± 4.03 kg/cm2) and 57 women without lymphedema (age, 53.68 ± 9.41 years; body mass index, 29.0 ± 5.44 kg/cm2) after unilateral surgery for breast cancer were included. Clinical and demographic information was noted. The severity of lymphedema with perimeter measurements (Frustum model), level of heaviness discomfort sensation with a visual analog scale, pain threshold with a digital algometer, shoulder-arm complex functionality with the Disabilities of the Arm, Shoulder, Hand Problems Survey (DASH), and scapular function with observational scapular dyskinesia and lateral scapular sliding tests were assessed. The t test, χ2 test, and Mann-Whitney U test were used for analyses.ResultsThe follow-up duration after the surgery was 4.24 ± 2.97 years and 3.19 ± 1.76 years, and the upper extremity volume was 2106.65 ± 510.82 cm3 and 1725.92 ± 342.49 cm³ in the lymphedema group and in the no-lymphedema group, respectively. In the lymphedema group, arm-heaviness discomfort, pain threshold levels in the trapezius and deltoid muscles, and DASH scores were worse (P < .05). The rate of scapular dyskinesia (70.0%) and type 2 scapula (32%) in the surgical side was higher in patients with lymphedema.ConclusionThe pain pressure threshold in the trapezius and deltoid muscles, heaviness sensation level, and inadequate upper extremity function are significantly higher in patients with lymphedema, and the scapular dyskinesia rate was higher.  相似文献   
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Context: To evaluate the stability provided by a new bilateral fixation technique using an in vitro investigation for posterior lumbar segmental instrumentation.

Design: Experimental cadaver study. In this study, we propose an alternative technique for a posterior lumbar fixation technique called “inferior-oblique transdiscal fixation” (IOTF).

Setting: Study performed at Engineering Center for Orthopedic Research Exellence (ECORE) in Toledo University-Ohio.

Participants: Six human lumbar cadaveric specimen used in this study.

Interventions: In this study, we propose an alternative technique for a posterior lumbar fixation technique called “inferior-oblique transdiscal fixation” (IOTF). As a novel contribution to the classical technique, the entry point of the screw is the supero-lateral point of the intersecting line drawn between the corpus and the pedicle of the upper vertebra. This approach enables the fixation of two adjacent vertebrae using a single screw on each side without utilizing connecting rods.

Outcome Measures: Flexion (Flex), extension (Ext), right and left lateral bending (LB & RB), and right and left axial rotation (LR & RR), and the position data were captured at each load step using the Optotrak motion measurement system and compared for IOTF and posterior transpedicular stabilization.

Results: The Posterior stabilization system (PSS) and IOTF significantly reduced the ROM of L4-L5 segment compared to intact segment’s ROM. During axial rotation (AR) IOTF fused index segment more than PSS. Besides this, addition of transforaminal lumbar interbody fusion (TLIF) cage improved the stabilization of IOTF system during flexion, extension and lateral bending. Whereas, PSS yielded better fusion results during extension compared to IOTF with and without interbody fusion cages.

Conclusions: We hypothesized that the new posterior bilateral system would significantly decrease motion compared to the intact spine. This cadaver study showed that the proposed new posterior fusion technique IOTF fused the index segment in a similar fashion to the classical pedicle screw fusion technique.  相似文献   
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